Applicator and Method for Applying a Lubricant/Sealer

ABSTRACT

A lubricant/sealer dispenser is disclosed for a component press-in system that includes a pressurized lubricant/sealer reservoir filled with lubricant/sealer. A nozzle is supplied with lubricant/sealer from the reservoir and includes an offset tip formed of PTFE that is enclosed in a steel tube. A controller controls a motor that rotates the nozzle within an opening in a part at a selected depth. The motor rotates the nozzle about a fixed axis and follows an inner surface of the opening as the part is moved by a robot relative to the nozzle in a selected pattern. The nozzle applies the lubricant/sealer by applying the lubricant/sealer onto the inner surface of the opening.

TECHNICAL FIELD

This disclosure relates to robotic assembly systems and the applicationof a lubricant/sealer to openings in a part before receiving assembledcomponents that are pressed into the openings.

BACKGROUND

Cylinder-heads, engine blocks, axles, differentials and other assembliesfor vehicles and other high volume cast parts were previously manuallyassembled or assembled with dedicated automation equipment at separatestations. Such cast parts include openings for assembled componentsincluding but not limited to caps, spark plug tubes, expansion cups,bearings, and the like. Assembled components are pressed into theopenings in the parts by independently controlled press tools.

Some assembly operations for parts such as cylinder heads requireapplication of a lubricant/sealer or lubricant/sealant (i.e. “Loctite™”)to lubricate an opening before assembled components are pressed into theopening. One prior method of applying the lubricant/sealer is to apply alow viscosity lubricant/sealer to a spinning disk that is held at aposition inside the opening and applying the lubricant/sealer bycentrifugal force to the inner diameter of the opening. Different sizedspinners must be used for different sized openings in the part with thisapproach. The use of low viscosity lubricant/sealers may result inobjectionable dripping or gaps in the lubricant/sealer applicationpattern. In addition, dedicated automation systems applylubricant/sealers in an early operation to, in some cases, twentyopenings to provide lubrication for pressing operations that may be twoor three stations after the lubrication application operation.Substantial delay after application of the lubricant/sealer allows timefor the lubricant/sealer to run down the side of an opening and maypotentially result in quality control issues.

This disclosure is directed to solving the above problems and otherproblems as summarized below.

SUMMARY

According to one aspect of this disclosure, a lubricant/sealer dispenseris disclosed for a component press-in system that includes a pressurizedlubricant/sealer reservoir filled with a supply of lubricant/sealer. Anozzle is supplied with lubricant/sealer from the pressurizedlubricant/sealer reservoir. A controller controls a motor to positionthe nozzle within an opening in a part at a selected depth. The motorrotates the nozzle about a fixed axis and follows an inner surface ofthe opening as the part is moved in a selected pattern by a robot toapply the lubricant/sealer by wicking (applying the lubricant/sealeronto the substrate surface by physical contact with the part) thelubricant/sealer onto the inner surface. The lubricant/sealer dispensercan accommodate a wide range of opening sizes and shapes becauserotation of the nozzle is coordinated with movement of the part by therobot.

According to another aspect of this disclosure, the nozzle may include abody portion concentric with the fixed axis of rotation of the nozzleand an offset tip extending radially outwardly from the axis ofrotation. The nozzle may be attached to a rotatable bracket with themotor rotating the nozzle with the bracket. The motor may be offset fromthe axis of rotation of the nozzle and may be connected to the bracketby a drive.

The lubricant/sealer dispenser may further comprise a robot controlsystem for controlling movement of the part by a robot that is alsointerfaced to control rotation of the nozzle and the flow oflubricant/sealer through the nozzle.

The pressurized lubricant/sealer reservoir may be an anaerobic systemthat includes a pressure regulator that controls the pressure within thereservoir. The robot controller controls a proportional regulator forthe reservoir.

According to another aspect of this disclosure, a method is disclosedfor applying a lubricant/sealer to a part prior to pressing componentsinto the part. The method includes the steps of transferring a part,such as a cylinder head, engine block or transmission housing, from apallet to a lubrication station and rotating a nozzle about a fixed axiswhile a robot moves the part in a predetermined path following anopening defined by the part. Rotation of the nozzle and moving the partin an orbital path allows the lubricant/sealer to be applied to a widerange of opening sizes and shapes. Lubricant/sealer is supplied to thenozzle and is applied by the nozzle onto an inner surface of theopening.

According to other aspects of the method, the step of transferring thepart from a pallet, to a lubrication applicator, and to a pressing toolis performed by a robot. The part may be moved in a circular path withina circular opening or may follow a non-circular path, such as an oval orsquared path, if the opening is non-circular.

The method may further comprise moving the part to an assembly locationwith the lubricant/sealer on the inner surface and pressing a componentinto the opening. The method may further comprise moving the partrepeatedly between the assembly location and the lubrication station.The part may be moved in a path following a second opening in the partto apply the lubricant/sealer from the rotating nozzle onto an innersurface of the second opening.

The above aspects of this disclosure and other aspects will be describedbelow with reference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front elevation view of a robotic component press-in system.

FIG. 2 is a top plan view of a robotic component press-in system.

FIG. 3 is a perspective view of a pressing tool attachment for therobotic component press-in system.

FIG. 4 is a perspective view of a lubricant/sealer applicator roboticcomponent press-in system.

FIG. 5 is a perspective view of a lubricant/sealer applicator of FIG. 4shown applying a lubricant/sealer to a part.

DETAILED DESCRIPTION

The illustrated embodiments are disclosed with reference to thedrawings. However, it is to be understood that the disclosed embodimentsare intended to be merely examples that may be embodied in various andalternative forms. The figures are not necessarily to scale and somefeatures may be exaggerated or minimized to show details of particularcomponents. The specific structural and functional details disclosed arenot to be interpreted as limiting, but as a representative basis forteaching one skilled in the art how to practice the disclosed concepts.

Referring to FIGS. 1-3, a component press-in system 10 is shown that maybe used to press components such as caps, spark plug tubes, expansioncups, bearings, and the like, into parts such as cylinder-heads, engineblocks, axles, differentials and other assemblies for vehicles and otherhigh volume cast parts. The component press-in system 10 includes afirst robot 12 that manipulates a part 14, for example a cylinder head,by taking the part 14 from a conveyor 16 that supplies the part 14 tothe system 10 on a pallet 18. As shown in FIG. 3, a second robot 20 isprovided with an end effector including a pressing tool 22 for pressingcomponents 24 into openings 26 defined by the part 14.

A reaction force bridge 28 is attached to a base 30 and is used tocounteract the reaction force that is created when the pressing tool 22presses a component 24 into the part 14. A press fixture table 32supports the part 14 above the base 30 while the pressing tool 22presses components 24 into the part 14.

A lubricant/sealer applicator 36 is shown as part of the system 10 inFIGS. 1 and 2 that receives lubricant/sealer from a lubricant/sealerreservoir 38. The fluid reservoir 38 is pressurized and provides ananaerobic flow of a lubricant/sealer such as Locktite™. Thelubricant/sealer applicator 36 is described in greater detail below withreference to FIGS. 4 and 5.

Referring to FIG. 3, the pressing tool 22 is manipulated by the secondrobot to select components 24 from a tray (not shown) that is part ofthe pallet 18, shown in FIG. 1, used to transport the part 14. Thepressing tool 22 is provided with quick connect tool changers (notshown) and selects a pressing tool from a magazine (not shown) thatcorresponds to the component 24 to be pressed into the part 14. Thepressing tool 22 may have one or more press actuators 39 that includevacuum or mechanical systems for retaining the tool and the components24 as they are moved into position to be pressed into the part 14.

Referring to FIGS. 4 and 5, a lubricant/sealer supply tube 40 providesthe lubricant/sealer to the lubricant/sealer applicator 36 from thereservoir 38. A drive 42 is provided to rotate the lubricant/sealerapplicator 36. The lubricant/sealer applicator 36 is attached by abracket 44 to a beam or frame of the component press-in system 10.

The lubricant/sealer applicator 36 includes an on/off valve 48 forcontrolling the flow of the lubricant/sealer through the applicator 36.

A spring assembly 50 retains a nozzle 52 resiliently to allow the nozzleto flexibly engage the part 14. The nozzle 52 includes a steel tube 54containing and supporting a polytetrafluoroethylene (PTFE) tube 56 thatcontacts the opening 26 in the part 14 to apply a bead 62 oflubricant/sealer directly on the part 14 by applying thelubricant/sealer on a sidewall of the opening 26. The soft PTFE tubeprevents scratching the inner surface 64, or sidewall, of the opening26.

The nozzle 52 rotates about a fixed axis of rotation while the part 14is moved by the first robot 12 in a path that follows the sidewall 64 ina continuous path. This arrangement allows the nozzle 52 to apply thelubricant/sealer to the surface of a larger opening with the axis ofrotation being within the opening 26. For openings that are smaller thanthe radial size of the nozzle 52, the part 14 may be manipulated withthe axis of rotation of the nozzle 52 being disposed outside the opening26 with only the tip of the tube 56 extending into the opening 26. Thesingle nozzle feature is enabled by the coordinating the movements ofthe nozzle 52 and movement of the part 14 by the first robot 12.

Rotation of the nozzle 52 and orbital movement of the part 14 arecoordinated by a single robot controller that may be programmed toinclude the location and size of the openings 26 for a part 14.Alternatively, the robot controller may have a look-up table that isreferenced for particular opening 26 parameters such as the location andsize of the openings 26. The robot controller also controls tool andcomponent 24 selection and the pressing operation.

The embodiments described above are specific examples that do notdescribe all possible forms of the disclosure. The features of theillustrated embodiments may be combined to form further embodiments ofthe disclosed concepts. The words used in the specification are words ofdescription rather than limitation. The scope of the following claims isbroader than the specifically disclosed embodiments and also includesmodifications of the illustrated embodiments.

What is claimed is:
 1. A lubricant/sealer dispenser system comprising: apressurized reservoir containing a lubricant/sealer; a nozzle receivingthe lubricant/sealer from the pressurized reservoir; a motor configuredto rotate the nozzle within an opening in a part at a selected depthwithin the opening; and a robot moving the part relative to the nozzlewith the nozzle following an inner surface of the opening to apply thelubricant/sealer by applying the lubricant/sealer onto the innersurface.
 2. The lubricant/sealer dispenser system of claim 1 wherein thenozzle includes a body portion concentric with an axis of rotation ofthe nozzle and an offset tip extending radially outwardly from the axisof rotation.
 3. The lubricant/sealer dispenser system of claim 2 furthercomprising: a valve receiving the lubricant/sealer from the pressurizedreservoir and providing the lubricant/sealer to the nozzle are attachedto a bracket, and wherein the motor rotates the valve, the nozzle andthe bracket as a unit.
 4. The lubricant/sealer dispenser system of claim3 wherein the motor is offset from the axis of rotation of the nozzleand is connected to the bracket by a drive apparatus.
 5. Thelubricant/sealer dispenser system of claim 1 further comprising: a robotcontrol system controlling movement of the part relative to the nozzleby the robot, wherein the motor that rotates the nozzle is interfacedwith the robot control system that controls a rotational speed of thenozzle and lubricant/sealer flow to the nozzle.
 6. The lubricant/sealerdispenser system of claim 5 wherein the robot moves the part between apallet, the lubricant/sealer dispensing system, and a pressing tool,wherein the robot control system controls the robot.
 7. A method ofapplying a lubricant/sealer to a part comprising: transferring a partfrom a pallet to a lubrication station; rotating a nozzle about a fixedaxis; moving the part in a path with the nozzle following an openingdefined by the part; supplying the lubricant/sealer to the nozzle; andapplying the lubricant/sealer from the nozzle onto an inner surface ofthe opening.
 8. The method of claim 7 further comprising: retaining thepart with a robot during the transferring step and moving the part withthe robot in a predefined path relative to the nozzle during the wickingstep.
 9. The method of claim 7 wherein the path is a circular pathwithin the opening in the part, and wherein the opening in the part iscircular.
 10. The method of claim 7 further comprising: moving the partto a pressing tool with the lubricant/sealer on the inner surface of theopening; and pressing a component into the opening.
 11. The method ofclaim 10 further comprising: moving the part from an assembly locationto the lubrication station; rotating the nozzle about a fixed axis;moving the part in a second path following a second opening defined bythe part; supplying the lubricant/sealer to the nozzle; and applying thelubricant/sealer from the nozzle onto an inner surface of the secondopening.
 12. The method of claim 7 further comprising: the part defininga second opening; and applying the lubricant/sealer from the nozzle ontoa second inner surface of the second opening defined by the part. 13.The method of claim 7 wherein the part is moved by a robot in thetransferring step, and wherein the robot moves the part along the pathfollowing the opening.
 14. The method of claim 7 further comprising:flexing the nozzle against a biasing force applied by a spring thatbiases the nozzle into engagement with the inner surface of the opening.15. The method of claim 7 further comprising: controllinglubricant/sealer flow to the nozzle with a valve that opens and closesto control lubricant/sealer flow to the nozzle wherein thelubricant/sealer flow is specific to the size of the opening.